One form of conventional combination lock makes use of numerals in the form of the digits from 0 to 9 to indicate the position of the rotatable wheels whose relative orientations determine whether the lock is open or closed. Another common form of conventional combination padlock uses a rotatable inner part mounted in an outer housing with numerical indicia on one part and an indexing mark on the other; the open condition is achieved by sequentially rotating the inner part with respect to the housing in opposite clock senses so that the proper numbers line up with the indexing mark on the housing. A typical combination for such a lock might be 28 clockwise, 35 counterclockwise, and 17 clockwise, for example.
Such conventional locks using numerical indicia as the key to their operation are difficult to use for certain classes of people, namely for the farsighted or otherwise visually handicapped, and for those persons who have difficulty remembering numerical combinations. The latter class would include persons suffering various types of mental impairment, such as the retarded or very old, or young children who are not yet familiar with numbers. In addition, even some persons in the prime of life and not afflicted with any noticeable handicap have difficulty remembering numbers.
Probably the largest group of people who have difficulty using the conventional numerical combination padlock includes the large number of middle-aged men and women whose visual acuity has begun to decline. The loss of ability to see in dim light and the need to hold printed text far away to bring it into focus is familiar to everyone who reaches the age of 45 or so. A far-sighted person who has finished working out at a health club or gymnasium and has to fumble with a conventional lock with its typically small numbers in dim light, and in addition has trouble remembering the proper combination, knows the frustration involved.
There has been a long-felt need for a type of combination lock whose key is linked not with numbers, but with other forms of indicia which are easier to see and/or remember.
U.S. Pat. No. 4,560,164 to Darling concerns the cryptographic art and in particular deals with the problem of making mechanical puzzles more challenging and difficult to solve. Darling characterizes one of the deficiencies of the art in which he was working as "fixed connections [which] limited the number of variations which could occur in positioning or rearranging the various sub-elements, thereby limiting the difficulty of solving the puzzle." (Darling, column 1, lines 40-43). He goes on to explain that "[o]ne object of this invention is to provide a means of varying the connection among the various sub-elements of a cryptographic device so as to increase the variations which can occur in rearranging the various sub-elements (col. 1, lines 43-47). FIG. 13 of Darling depicts an alternate embodiment of his invention "suitable for actuating a locking mechanism," as he states in lines 62 and 63 of column 15. Earlier, in describing his "tubular, puzzle type of cryptographic device" (col. 1, lines 6 and 7), Darling states that "[t]he first stepped portion 52 of stepped ring 50 has a surface, which is preferably the outside or external surface, on which numbers, letters, symbols, colors, or other indicia 56 are located." (col. 6, lines 38-41 ).
U.S. Pat. No. 3,735,835 to Thomas discloses a locking means having "a cylindrical portion 112 marked with ciphers e.g. digits" (col. 2, lines 24 and 25). Thomas further discloses that "[t]o facilitate use at night, the ciphers may be marked in luminous or fluorescent paint material." (col. 3 lines 43-45). This apparently refers to the type of luminous paint employed in objects that glow in the dark and which commonly use a radioactive material mixed in a medium that emits light in response to absorption of the radioactive emissions. Thomas suggests that the "use at night" of a lock mechanism with conventional numerical indicia can be facilitated by marking the digits in luminous paint material so that they can be seen in the dark, as are the dials of a luminous wristwatch.
U.S. Pat. No. 1,238,247 to Baker et al. discloses a steering control lock for automobiles with a plurality of locking collars having "external characters" which are geometrical shapes (as shown in FIG. 1), such as circles, squares, and triangles.
U.S. Pat. No. 3,775,775 to Mazzenga is directed to a device for designating matching garments of a coordinated set of wearing apparel. Matching garments are identified with identical indicia, and Mazzenga depicts animal designs for the indicia in the case of childrens' clothes. Mazzenga explains part of the rationale for his invention as follows:
Children, however, frequently encounter difficulty in selecting the appropriate matching garments of a coordinated set as a result of their inexperience in discerning the minor differences which may distinguish the color, pattern and design of the respective garments. [Mazzenga, column 1, lines 11-16]
U.S. Pat. No. 1,391,986 to Smith is directed to an "educational appliance" intended to solve the problem of assisting "children . . . to spell words, to associate words with pictures appropriate thereto, to place parts of pictures in proper relation to form complete pictures, to add different sums and to spell different words . . . . " (Smith, col. 1, lines 14-20). Smith states that ". . . I prefer to form parts of each picture on two or more adjoining [rotatable] sections 2 . . . " (col. 2, lines 93-95). Smith's preference is clearly depicted in his FIG. 1.
U.S. Pat. No. 4,443,199 to Sakai is directed to "a teaching method and aid for teaching the pronunciation and spelling of any language . . . " (col. 2, lines 27-29). Sakai makes use of a "first set of displaceable units" which "visually or tangibly, individually, prominently, carry alphabet letters of the language" and a "second set of displaceable units" some of which "are individually colored to indicate a phonetic vowel of the language and others which are formed into different geometric shapes to represent specific consonants and diagraphs of the language." (col. 2, lines 54-61).
U.S. Pat. No. 4,650,421 to Anczurowski is directed to a method of representing colors to a blind person. Anczurowski uses combinations of sets of parallel straight lines which can be felt by the blind person because of being raised above a surface the color of which is being represented.
U.S. Pat. No. 4,684,945 to Sanderford is directed to an electronic lock controlled through a keyboard, the keys of which bear conventional numerical indicia (as shown for example, in FIG. 1).
French Patent 1,078,189 is directed to an improved coin bank with a plurality of rotatable ring sections whose orientation locks or unlocks the bank. Two of the ring sections bear numbers and playing card suit symbols, while the rest bear parts of a comprehensive scene or design which becomes recognizable when the bank is in the unlocked position.
None of the references described above discloses a combination lock bearing patches of daylight fluorescent colors with or without additional nonnumerical indicia to produce a combination lock that is easier for people to use and to see in daylight or under artificial lighting conditions.